Pan type mixers are used extensively for producing thorough mixing of ingredients such as those used to make concrete, glass, and other mixed substances. The present invention relates to mixers having a circular pan that cooperates with an axial rotating spindle carrying mixing blades or paddles that agitate the material being mixed. The material is confined in an annular trough formed between concentric upstanding walls. The disposition of the rotating paddles causes a braiding action of the materials being mixed, so that there is little liklihood of any unmixed material remaining in the mixing space provided the machine is operated a requisite period of time.
The invention is being applied to mixers of the above class which may run all the way from 1/2 cubic yard to 41/2 cubic yard batch capacity. Such large machines require a specially sturdy construction because of the heavy loads placed upon them. They are also subjected to extreme wear and because of their weight, must be well supported. Objections to machines previously used have included excessive mixing time, degradation of materials during mixing and inadequate strength and sturdiness to withstand the type of service frequently encountered. A further objection has been the over-all height, which increases the height of the charging apparatus used to load the mixer from a space above it.
The present invention substantially overcomes the above difficulties and results in improved performance, maintenance and life as well as more economical manufacture.